1. Field of the Invention
The present invention refers to the area of print finishing. It relates to a print finishing system as claimed in the preamble of claim 1. The present invention also relates to a method for operating such a print finishing system.
2. Discussion of Related Art
In modern printing operations, during the further processing of printed products which originate from rotary presses, high processing speeds and capacities are demanded. In addition, there is the desire for the most efficient use and full capacity utilization of the systems, this above all also in view of the relatively high investment costs of the printing press and conveying systems. At the same time, the further processing is also to enable a high level of flexibility so that as many end formats of pre-products, main products and/or part products as possible can be processed further by means of the same system. The conventional conveying and processing systems in printing operations are still based, in this case, on serial processing concepts. In this case, printed products or part products, etc. are transported in the majority of cases by means of conveying belts, feeders or the like on a conveying line, often as a shingle stream, and are supplied to processing systems. As rotary presses according to their operating principle generally print paper webs in a serial manner, processing the printed products further in a serial manner is obvious. A serial processing concept is also often imposed as a result of the operating steps during further processing requiring a serial sequence. Accordingly, up to now conventional conveying and processing systems have remained restrained by said serial principle.
To increase the processing capacity, it has been proposed many times during further print processing to divide the printed product stream into several part streams by means of points. Such an apparatus is described, for example, in Patent Application CH 04 668/86. By using buffer devices, one or more continuous streams of printed products are divided into supply sections of at least two processing stations. Another method as claimed in Patent CH 649 063 shows how a conveying track is divided into several tracks in order “to be able to use the known and proven conveying technology”. This is meant to achieve the object of maintaining the output of the suppliers, called feeders in the document, whilst retaining the mentioned conveying technology. The required processing capacity is divided into several transporting or processing paths which, for their part, once again use a purely serial conveying method. The disadvantage of dividing the conveying tracks is that along with a large space requirement for the separate lines, each of said lines requires its own processing means, etc. Consequently, expenditure on machines and organization is actually duplicated.
In the production of complex products where, if need be, parts of the products are also sewn, bonded, trimmed, coated, addressed, provided with stick-on labels or processed in another way, up to now in a corresponding manner many collating apparatuses have had to be set up and operated. This meant a large amount of expenditure on apparatuses and resulted in a correspondingly increased requirement for space.
An example of a device for processing printed products which is suitable for the production of complex, multi-part printed products is known from EP 0681979. Printed products are collected using at least one collecting drum. For carrying out certain processing steps on the printed products or for adding additional products to the printed products, said printed products are guided out of the collecting drum into a whirling arm. The printed products, in this case, retain their state in an unchanged manner when transferring from the processing drum to the whirling arm and from the whirling arm to the processing drum. They consequently do not “note” whether they are situated in the processing drum or in the whirling arm. As the whirling arm can be guided along a practically arbitrary movement path, there is the possibility for the most varied processing steps. The whirling arm offers, in particular, the possibility of guiding the printed products away from the processing drum for the execution of special processing steps or the supplying of additional products and of returning them again to said processing drum for further processing. As a further particular advantage, EP 0681979 provides that the whirling arm enables the transferring of the printed products from one processing drum to another, during the transfer the processing of the printed products or the supplying of additional products being made possible. In addition, the present invention makes possible the carrying out of special processing steps or the addition of additional products in the supply to the processing drum or in the guiding away from the processing drum, the serial processing mode always being retained, that is to say all the printed products in the product stream inside and outside the drum run through the same conveying belt and consequently the same processing steps and are processed strictly in a serial manner. This is so even in the case of embodiments where the printed products are guided from the drum to the whirling arm and back to the processing drum.